Audible telephonic line identification



' A ATTORNEY March 7, 1950 1 M. PoTTs 2,499,776

AUDIBLE 'TELEPHONIC LINE IDENTIFICATION Filed May 27, 194e 2 sheets-sheet 1 am 41 48 49 5 5 5 6 f 5, 5 3 22 53 l -el 54 l 62 sa 59 I e3 2:5 I se i 64 Y -eo es 6'? l 251, f-n 72- 5B I l 58 I 26N I se sa es 7 Il Y L74 I 76 271 l l I 28j l y ^/\/\/v3 29 6R.. n gul?) uP 56X va e L Isa |49 6\ a2 8 U1- les n3 Ish K k 83 s s79 |48 l09 j |13 l I ||8 m l' s u "7 A74 o 12E-d "s |a|-\ L56 U7 "la |46 -P Lm? /'|64 UNSS |67 96\ Lal FIG. l

' -mvENToR LOUIS 4M. POTTS, 'DECEASED MARTHA W. C. POTTS, EXECUTRIX BY l March 7,1950 I jM, POTTS 2,499,776

AUDIBLE TELEPHONIC LINE IDENTIFICATION Filed May 27, 194e 2 sheets-*sheet 2 l ouTGolNs cmcun Il.- J

- |NvENToR l 92 9a LOUISl M. POTTS, Dl-:cEAsl-:D

MARTHA w.c.PoTTs, ExEcuTRlx on 99 Patented Mar. 7, 1950 AUDIBLE TELEPHONIC" LINE IDENTIFICATION Louis M. Potts, deceased, late-of Evanston, I-ll., by Martha W. C. Potts, executrix, Evanston, Ill.,A `assgnor to Teletype Corporation, Chicago, Ill.,

a corporation of Delaware Application May 27, 1946, Serial No. 672,467

4 Claims. (Cl. 179-27.)

The present invention relates totelephone systems, and more particularly to line identifiers for use therewith.

In present day telephone systems it is necessary in the making of toll or long distance calls to summon ari-operator Yin order to complete a call through to the called subscriber. It is then the operators duty not only to complete the connection for the call, but to make `out a toll ticket bearing suiiicient information so `that the correct charge may be arrived at and the calling subscriber billed accordingly. In order to have sucient information the operator must, obviously, know the number .of the calling: subscriber, which is generally obtained by requesting the calling subscriber to repeat it to the operator. There is, of course, always a chance that a subscriber may give the operator an incorrect number, resulting in `improper and incorrect billing to a subscriber.

Likewise, where automatic toll ticketing apparatus is utilized it is desirable that some type of apparatus be provided whereby the calling subscriber may be identied in order that correct billing may result.

Accordingly, it is .an `object of the present invention `to provide` mechanism for automatically indicating the calling subscribers number.

A further object of the invention is to provide an audible line identifier for achieving such function.

Still another object of the invention is to provide line identifier mechanism which may be incorporated with standard telephone circuits or systems.

Yet another object of the invention is to` provide photographic films` bearing visual representations of audible tone frequency designations of calling subscribers exchange and numbers in combination with photoelectric `cells and a set of distributors Whose segments arel predeterminedly associated with individual subscribers so as to render effective at .one ltime only the designation of the calling subscriber.

The present invention. is hereinafter described as incorporated in a standard panel dial switching system, only suiiicient of Which is described as is necessary to `understand the presentv invention. It is obvious, however, that the invention is` `not limited to application with such` a System,

2 but may be utilized in other standard telephone switching systems.

The apparatus, in general, includes a plurality of storage recorders for telephonic retransmission of exchange designations and subscribers numbers in combination with a set ro1 distributors Whose segments are` predeterminedly associated with individual subscribers in such a manner as to render effective lones only of said re* corders which correspond to the exchange `designation and integers for identifying the corre` spending individual subscribers. The storage recorders consist .of photographic lms bearing a visual representation of audible tone frequency designations and an Aassociated photocell responsive to such designations.

The features and advantages of the present invention will become apparent from the following detailed description of an embodiment thereof, when read in `conjunction with the accompanying drawings, in which:

Figs. 1 and 2 illustrate a telephone system incorporating .therein line identifying mechanism and circuits, and should be viewed together from left to right;

Fig. 3 is an 4enlarged detail View of part of the line identifying mechanism; and

Fig. 4 is an enlarged portion of a section of iilm used with the line identiiier.

The following description will only refer to so much oi the telephone system as is necessary for a complete understanding of the invention, as such system is of the standard panel dial type, which is well `known to those versed in the art.

` Referring now to Figs. l and 2 the line identider apparatus I I is shown in conjunction with a panelv dial telephone system which includes a calling subscribers station indicated generally by the numeral I2, line finder district and incoming circuits indicated generally by the numeral I3 which extend a circuit to an operators `circuit indicated generally as I4 (Fig. Z) and which includes an operators cord circuit indicated generally as IB and anoperators head set indicated generally as Il. The circuit may `further be traced from the operators circuit -IB over an outgoing circuit indicated generally as I8 ,to a called subscribers station indicated generally as I9. y

. 'I he above telephone equipment .operates in a standard manner as is well known in the art and results in the operator responding to the dialing of an operators call signal by a calling subscriber, the operator learning the identity of the calling and called subscriber and thereafter extending the call through the necessary switching equipment to the desired called subscriber.

The specic line identifier mechanism utilized with the above circuits will first be described generally and thereafter in conjunction with the telephone circuits.

With reference to Fig. 1 particularly, the line identifier il comprises a plurality of films 2| to 3l, inclusive. The lm 2l is divided into portions of three sections on each portion of which is provided in audible tone frequency designations the three symbols indicative f a particular exchange, such, for example, as the call letters BUC in the exchange Buckingham. Fig. 4 is an enlarged view of a portion of the lm 2| and a shows thereon a portion of the audible tone frequency designation for the letter B.

Each of the films 22 to 3| inclusive has the integers l) and l to 9, inclusive, photographed thereon in audible tone frequency designations, as for example, the film 22 may have the integer 0 photographed thereon reoccurring many times, the nlm 23, the integer I, and so on to the integer 9 on lm 3 I.

Such film, as 2l for instance, may be seen more clearly in Fig. 3 wherein it is to be noted the lm is provided with feed holes 33 which cooperate with feed pins 34 provided on the periphery of a feed sprocket 39 secured to a shaft 31 which is driven continuously by any suitable means, not shown. The shaft 31 is provided with a plurality of feed sprockets such as 39 which cooperate individually with each of the films 2l to 3l, inclusive.

The film 2l is in the form of a continuous loop and passes over an idler roller 38 which is loosely mounted on a shaft 39 and which serves to keep the film 2| relatively taut. As was true with respect to the feed sprockets 36, there are a plurality of idler rolls 38 on the shaft 39 each of which is associated with one of the films 2l to 3 l inclusive.

Referring again to Fig. 1, it may be seen that a photocell 4l is provided adjacent to each of the films which is connected in circuit with a suitable amplifier 42, associated with the particular photocell. As may be seen in Fig. 3, a light source 3 is provided which through a suitable converging lens 44 directs the light to an opening 49 in a guideway 41 through which the nlm passes. The photocell 4I is provided on the opposite side of the film from the light source 43 and lens 94 and thus as the lm passes the opening 59. the photocell 4l is activated in accordance with the audible tone frequency designations on the particular film.

Referring again to Fig. 1. it may be seen that the photocell 4I and amplifier 42 associated with the film 2l is connected by means of a conductor 48 to a distributor ring 49 which .is provided with a conducting section i forming approximately one-third of the length thereof and an insulated section 52 occupying approximately two-thirds of the ring 49. The ring 49 is connected electrically by a pair of brushes 53 of a common brush arm 54 to a solid ring 55 which h as a conductor 56 extending therefrom.

The photocells il and amplifiers 42 associated with the integer f llms 22 to 3l, inclusive, are connected to a plurality of common conductors 60 4 which in turn are connected to distributors similar' to that described above. The common conductors 69 are ten in number, one of such conductors being connected with the photocell iii and amplifier 0.2 associated with the zero integer film 22, and so forth, the last conductor 99 being connected to the photocell All and amplifier 42 associated with the lm 3i which bears audible tone frequency designations thereon of the integer 9.

As a specific example, it may be seen that seemented ring 51 has insulated portions 58 and small uninsulated segments 59 the latter of which are connected to the common conductors 99 designating the integers i and l by the conductors 6I and 52, respectively. The distributor' ring 51 is also provided with small segments t3 which are grounded over an obvious circuit. The distributor ring 51 is connected electrically by means of a pair of brushes tt of the common brush holder 54 to a solid ring 55 from which extends a conductor E1.

In the specific instant example attention is also directed to a segmented distributor ring E59 which has similar insulated sections 53 as has the ring 51 and which has two small segments 69 connected to the common conductor til indicative of the integer 2 by means of a conductor 1l. In this case the small segments 69 are in aligned position with the grounded segments 93 of the ring 51. The ring 68 is provided with two grounded segments 12 which are in a position of alignment with the segments 59 of the ring 51, previously described as being connected to the common conductors B9 indicative of the integers i and 9. The ring 68 is connected electrically by a pair of brushes 13 on the common brush holder 5d to a solid ring 19 which has a conductor '1t extending therefrom.

It should be noted that in the above example only two pairs of integer distributor rings have been described whereas four have been illustrated in Fig. 1. In the present invention it is proposed to provide one hundred sets of distributor rings such as 51 and 66, and the undescribed r pair immediately therebelow, in order that in the rotation of the common brush arm or arms 5t, signals may be generated indicative of all possible combinations of the thousands and hundreds integers of a telephone number from 00 to 99 inclusive. Likewise, it is proposed to provide one hundred sets of rings similar to rings 5S and 14, and the undescribed pair immediately therebelow, in order that designations indicative of all possible combinations of tens and units integers that may occur in a telephone number from 00 to 99 may be generated. l

It should also be noted that the various distributors are predeterminedly wired to individual subscribers, one each of the thousands, hundreds and tens units distributors being joined. In this manner a complete four digit number will always be transmitted, and because of the predetermined wiring the same number will always be transmitted for the same calling subscriber. y

Under the above described illustration it is to be remembered that the integers l. 9 were described as the thousands, hundreds integers and 2, 2 were described as the tens and units integers, along with the previous description of the exchange designation as BUC. Accordingly, in the present example it is proposed that the designation of the calling station l2 be BUC 1022. as dcribed above and as will be mentioned hereina er.

Thus, with the inclusion of one hundred thousands, hundreds integer distributors and one hundred tens, units integer distributors and a single exchange designation it is possible to provide numbers indicative of calling stations to the extent of any combinations of four digit numbers in a particular exchange. It is obvious, however, that by providing a diiTerent type distributor and a greater number thereof it is possible to extend such use to telephone numbers having a number of digits greater than four.

As a further example, by tracing the connections from the common conductors 5B to the two sets or pairs ofdistributors not described in detail, it may be seen that they would be connected to a calling subscriber `having the telephone` designation BUC 9945.

It is now deemed advisable to describe more in detail the telephone circuit in conjunction with which the line identifier is utilized and thereafter -provide `a description of the combined apparatus from an operational standpoint.

In the following description let it be assumed that the calling subscriber I2 has dialed his apparatus with the code or codes indicative of the operator which will result in the line finder dis-- trict and incoming circuits I3 operating `to complete an electrical circuit over the conductors 'I'I extending from the calling subscriber I2 to the tip 'IB and ring 'i9 connections in the line finder district. Thereafter the circuit may be extended from the tip connection I8 over a conductor 8|, through the upper right-hand winding of a repeating coil 32 to ground, and thence over battery 83, through the lower right-hand winding of the repeating coil 82 and through a resistor and over a conductor 84 to the ring connection i9.

Further tracing of the circuit through the line finder district and incoming circuits I3 may be from the upper left-hand winding of the repeating coil 82, over a conductor 8.6, through the lower left-hand winding of a repeating coil 81, through a condenser and the `upper left-hand winding of the repeating coil 81 and over a conductor 83 to the lower left-hand winding `of the repeater coil 82.

Further tracing of the circuit from the line nder district and incoming circuit I3 may be had from battery 89, through the lower righthand winding of the repeating coil 3l, over a conductor 9|, through the winding of an alternating current relay 92, through. a condenser 93, over conductors 94 and 96, and through the upper right-hand winding of the repeating coil 8l' to ground. Such circuit is thus extended to the operators cord circuit or position I4 wherein the resulting energization of the alternating current relay 92 will result in the attraction of its armature 9i completing a circuit from grounded battery 98, `through the armature 91 over a conductor 9S and through the lament of a `light bulb II to ground. The lightbulb` lili will immediately become illuminated indicating to the operator that a calling subscriber desires telephonic interconnection.

Upon the operator noting the illumination of thebulb HEI, the plug |02 will be inserted in the associated jack ID3 resulting inthe opening oi `the connection between conductors 94 and `96, thereby causing the alternating current relay 92 to become de-energized and the bulb II to be extinguished. Upon the connection of the jack and plug the circuit from calling subscriber i2 is extended to the operators cord circuit .Ill and more particularly to the talking circuit I1 in `a conventional manner.

At the time that the above circuit is extended from the calling subscriber I2 to the operators talking circuit Il, a relay `H34 (Fig. l) connected across the conductor 84 will `be energized resulting in its attracting associated armatures, one of which is designated as |06. However, the attraction of `the armature Iil will have no effect at this time but will be eiective at a future time, as will be described hereinafter.

Prior to the connection with the operator .and the dialing ci the operators number, but after the calling subscriber I2 removes his receiver, the two left-hand windings of aout-oli relay |01 connected to the sleeve connector Hi8 over a conductor iilil become energized resulting in the attraction oi three armatures III, IIZ, and IIS. The relay It? has also been provided with an added third or right winding.

Upon the completion oi the circuit from the calling subscriber i2 to the operators head set circuit Il, as described, audible tone signals from i the line identi'ner il will be impressed over that circuit in order that the operator may be apprised as to the station designation oi the caliing subscriber i2, namely BUC 1022 in the instant example.

It should be noted that the various nlm-s, photocells 4I, amplifiers 42, and distributors operate continuously to impress audible tone signals on their'asscciated conductors. However, such signals will oniy be impressedon the telephone circuit when a calling subscriber initiates a call through the operator as the two left-hand windings ci the cut-oir relay iti will not be energized until this time. Such audible tone signals will then continue on the circuit, repeated con-n tinuously, unless the calling subscriber abandons the call (relay H31 de-energa'es) or `the operator causes the operation of certain apparatus, as will be `described hereinafter.

In the following description let it be assumed that the operators talking circuit I'l is connected in the circuit at a time when the distributor brushes 53 commence to traverse the uninsulatedv segment 5I of the segmented distributor ring 49. It should be noted that the film 2i and the brushes 53 operate in such a timed relation that the three portions of the i'llm 2l comprising the exchange designation BUC will pass the opening iii in the guide `Iii and cause a corresponding activation of the photocell M during the time that the `brushes 53 pass over the uninsulated segment 5I. Now, assuming that at the time of the connection the brushes 5t start to transverse the uninsulated segment 5I the photocell Lil and amplifier lili will operate to impress audible tone signals on the conductor i3 to the uninsulated segment 5I, which are then impressed by means of brushes 53, solid ring 55 and conductor 56 to junction point H4, thence over a conductor IIS, through the unattracted armature III of a relay Ii, over a conductor H9 with which it is in engagement, through a condenser I2I to junction point I22 of the conductor 34, previously described. 'in this manner audible tone signals indicative of the station designation BUC will be impressed to the repeating coil alli, and thence over the previously described circuit to the 0perators talking circuit VI.

During the time that the brushes 53 are traversing the uninsulated portion 5I the brushes associated with the various other distributor rings provided for the thousands, hundreds integers and tens and units integers will be traversing their respective rings but will be passing over the large insulated portion 58 thereof and thus no integer designations will result.

As the brushes 53 pass to the insulated section 52 of the distributor ring 49 the brushes B4 will pass from the large insulated portion 58 of the distributor ring 51 to the iirst of the two small segments 59 connected by conductors 9| and 62 respectively to two of the common conductors 60. As the brushes 64 traverse the two short segments 59 in succession audible tones indicative of the integers I and will be impressed from the second and iirst common conductors 59, respectively, over the conductors 6| and 62 to the two small segments 59, thence over the brushes 94 to the solid ring 96, over the conductor 51, through the armature H3 which is now held in its attracted or left-hand position due to the energization of the two left windings of the relay |01, over a conductor |23, through the added or right-hand winding of the cut-off relay |01, through a resistor and over the conductor 10 to the solid distributor ring 14, over the brushes 13, which are traversing the short segments 12 at the same time as the brushes 64 traverse the short segments 59, to ground. Thus, audible tone signals are impressed in the right-hand winding of the three winding relay |01 indicative of the integers 0.

It should be noted that during the time that the operation described above is occurring; that is, with the distributor brushes traversing the iirst two short segments of their respective segmented distributor rings, the only audible tones which can possibly be transmitted over the described circuits are those of the integers 0, because only one pair of thousands, hundreds distributor rings such as 59 and 66 will be so connected to the calling subscribers circuit and all of the pairs of distributor rings associated with the tens, units integers will have their two rst short segments grounded rather than being connected to any of the common conductors 69.

The audible tone signals were just traced as passing through the right-hand winding of the relay |01, which will energize in accordance therewith and will superimpose corresponding tone frequencies to the two left-hand windings thereof resulting in a circuit which may be traced from the left-hand windings of the relay |01, over the conductor |09 to the sleeve connection |09, and thence through a condenser |24, over the conductor H6, through the armature ||1 (still in its unattracted position), over the conductor II9 in engagement therewith, through the condenser |2I to junction point |22, and thence through the unnumbered resistor to the repeater coil 82. Thus, at this time the audible tone signals indicative of the integers i, 0 will be impressed over the previously described circuits to the operators talking circuit |1 to apprise her of the thousands and hundreds integers in the calling subscribers number.

The condenser |24 has been provided in order that the exchange designation, previously described as being impressed on the conductor 56 to the junction point lill with the conductor H5, may not cause a backup circuit to the sleeve connection |08.

After the brushes 54 have traversed the two short segments 59 causing the described audible tones to be impressed on the circuit they will traverse the short insulated segment 58 which is provided on all of the segmented integer distributor rings. Such has been provided inasmuch as the brushes are traversing the distributors at a rate one-third of that that the films 2| to 3|, inclusive, are passing the opening 49 and activating their corresponding associated photocells 4|, and therefore for timing purposes and to insure the proper tone generation, short insulated segment 58 has been provided after the thousands and hundreds integers have been impressed on the circuit. As the various brushes traverse the short insulated segment 58 no signals will be impressed on any of the circuits.

As the brushes 64 further traverse the segmented ring 51 they will pass over the two short grounded segments 93. However, inasmuch as these segments are not connected to any of the common conductors 60 it is obvious that no audible tone signals will result from the cooperation therewith by the brushes E4.

However, as the brushes I3 associated with the segmented distributor ring 68, which are correspondingly timed with the brushes 64, pass over the two short segments 99 audible tone signals will be impressed over previously described circuits which may be traced from the third common conductor 60 indicative of the integer 2, over the conductor 1|, through the two short segments l|59, over the brushes 13 to the solid ring 14, over the conductor 16, through a resistor, through the added or right-hand winding of the cutoi relay |01, over the conductor |23, through the armature I|3 now in its attracted position, over the conductor 61 to the solid ring 66, through the brushes 94 which as described are at this time traversing the short segments 63, to ground. Thus, during this interval the right-hand winding of the cutoi relay |01 will be operated in accordance with audible tone frequency designations for integers of the tens and unit positions which in the present example have been described as being the integers 2, 2.

At this time the alternating current in the right-hand winding of the relay |01 will be induced in the two left-hand windings thereof, and will be superimposed on the normal direct current resulting in audible tone signals being impressed over the previously described circuits; that is, over'conductor |09 to sleeve connection |08, through the condenser |24, over the conductor |I6, through the armature |I1 in its unattracted position, over the conductor H9, through the condenser I 2| to junction point |22, through a resistor and the right-hand windings of the repeater coil B2 and thence over the described circuits to the operators talking circuit I1.

Thus, the operator will now receive audible tone signals indicative of the tens and units integers of the calling subscribers number. Inasmuch as, previously described, the operator already has received the exchange designation and the thousands and hundreds integers the operator now knows the entire designation of the calling subscriber I2 and may enter it on the toll ticket provided therefor.

Similarly as was described above, during the impression of the tens and units integers no other integers may be impressed on the circuits ybecause there is but a single distributor pair connected for a 2, 2 designation in the tens and units position and the brushes associated with the thousands and hundreds integer distributors are passing over grounded segments at such time.

andere lf 1no further operations were to occurat this `time the audible tone signals would be continuously generated and impressed to the operators talking circuit |1 in a manner as has just been described, until such time as the calling `subscriber decided to abandon the call or replace the receiver `on the hook. However, the operator is provided with special apparatus as will now be described. As may be seen in Fig. `-2 the operator is provided :with aspecial 'key or push button |26, which is normally in=its 'righthand position resulting in the completion ofthe circuit from ground, `through the lresistor' iand the condenser |21, through the key l|2|-l land through a resistor to grounded`batteryf|28. 'During the establishment of the-above circuit `with the key |26 in its normal position the condenser |21 will be chargedfrom the battery |28. After the operator has received the calling subscribers `station designation and indicated it onithetoll ticket the operator will cause the key `or push button `We to be moved toward the left resulting in the establishment of a circuit from ground, through the resistor `and condenser |21, through the key |25, over aiconductor |29, and through the winding of a relay |3| to ground. As soon as thekey ismoved to its left-hand -position'the condenser |21 `will dischargethrough the-winding of the relay |3| resulting iinsthisrelaybeing energized momentarily, or until *ithetcondenser `|21 discharges completely.

During thev `momentary. energization` of the Vrelay i`3| its armature |32 ywillbe attracted thereto resulting in the `con'ipletionofa circuit from conductor |33, vthrough `thearmature `|32 to :the

conductor |34, `which results in a currentsurge being generated in the talking circuiti|1 which is transmitted through the plug |02 and jack |03 to theconductors A9| and 96 causing Aa relay |35, Fig. l, to be energized, resultinginfits'armature |31 being attracted thereto.

During the normal operation -of the Ytelephone circuits a circuit is established which may be traced from grounded battery |38, through the left-hand winding of a `relay |30, `over 'a `cony ductor Mil, through the unattracted armature |33 of a relay |43 havingtwo'windings, over Aa conductor |44 to junction point |46, over a `conductor |41, through the upperlefthand winding oi `the repeater coil 81, over `the lconductor and through the lower left-hand Winding ofthe repeater coil 82, over a conductor |48, Vthrough the winding of 'a polarized relay |49, over aconductor 55|, through `the upper left-hand Winding of the repeater coil 82, over the conductor 86, through the lower left-hand winding of the repeater coil B1, over a conductor |52, through an unattracted armature |53 of `the `relay |43, over a conductor |54 and through the right-hand winding of the double winding relay |139 "to ground. This `is the normal condition for `the polarized relay M9, asis Well known inithetele- -phone art, and which is utilized as a register relay i43 will'thus Abecome energized causingits `win-ding of the relay |39'to ground.

one Iof the repeater `coils tothe other. Ftiallydescribed circuit `tor polarized relay |549 is `broken `at armatures |542 and |53 as they are armatures |42 and |53 to `,be attracted-thereto.

Asfaresult Yof the attraction of the armature i|l42 -a circuit willbe established which maybe `traced from groundedbattery 30, through the leftehand winding of relay |30, offer conductor `|4|, through `the armature "U42, over a conductor 6|, through a sequence switch |62 which is now -lin 4its closed condition, over conductors |63 and L| 52, 'throughfthe lower'left-hand winding of the repeater-coil 8-1, rover the `conductor S5 to the upperleft-hand lwinding of the repeater coil 82,

`over `the conductor |5|, through the winding of the polarized relay |43, over the conductor |48 and throughfthe lower left-hand winding `of `the repeater coil 82, over the conductor 80, through the `upper left-handwinding of the repeater coil v'181, over `the conductor `|41 to junction pointj |45, over a conductor P64 andthrough `the selector switch which is in its closed condition, over acon'ductor |61. through -the arroature |153 which Ais `novvin its attracted or left-hand position-lover the conductor |54 and `through'the right-hand Such reversalY of current inthe winding of the polarized relay |49 results in that relay becoming energized and attracting its armature |68 thereto. `It might be noted that `the condensers anein- -iserted between the upper and lower left-hand windings ofthe repeater coilsi-82 and 81 in order `that the currentijust described may not pass from The iniattracted.

As a `result of .the fenergization of the polarized relay V`|49, `which in the instant case will befor a Very/short time induration and during which -time the A'register which it normally operates `will be suppressed from operation, an electrical cirlcuit `is established-which may be traced from ground, through-the -armature |58, over a conductor |69, and through the right-hand winding The relay cause 4the `attraction of the associated `armature |i1| 'which resultslin thel establishment of a locking electrical circuit which be traced from grounded battery i12, through a resistor and fthe-left-h-and winding `of the relay H3. `over a conductor |13, through the varmature |1| now 'in its attracted position, over a conductor |14,

and through theiarmature |00 which is in its attracted `or right-hand position'due to the energization of thefrelay |04 to ground. YSuch circuit supplies locking current for the relay `||8,

holding it in `its energized condition "with its armature ||1 attracted thereto or `toward the fleft, until such time as will be described hereinafter.

As a result ofthe energization of the `relayl |.8 andthe attraction of the armature ||1 thereto, the circuitisbroken between the conductors |-6 and `I'ISJ over the armature |1, which was previ- `ously described as forming part of the circuit over which the audible tone signals for both. the

`exchange BUC and the number 1022 were traced. `Thereforeunder this condition the audible tone signals are no longer impressed over the line finder and incoming' circuits I3 to the operators talking Vcircuit l1 butinstead are cut off `before they reachv'the telephone circuit.

After theabove has'occurred` the operator `will l1 cause switch or key |16 (Fig. 2) to be moved from its normal or illustrated position to a position whereat the connectors thereof will be removed from engagement with the associated contact swinger members. Under this condition the contact swingers |11 are free to move to their relaxed or inner positions resulting in the establishment of an electrical circuit which may be traced from the telephone dial |18 which is standard equipment, over the conductor |19 to the right-hand swinger |11, and over a conductor |8I to plug member |82 associated with the jack |83. The circuit may be further traced from the opposite side of jack |83, through the plug |82, over a conductor |84, through the left-hand movable swinger |11 and over a conductor |86 to the telephone dial |18. Inasmuch as the jack |83 serves as a connecting link between the outgoing circuits I8 and the called subscribers station I9 the dial |18 will thus be placed in circuit therewith and the operator may dial the number of the called subscriber in accordance with the request of the calling subscriber. .At such time as the called subscriber answers the operator will be aware thereof as is standard telephone practice.

At such time as the called subscriber acknowledges the call the operator replaces the switch or key |16 to its normal or unoperated position at which time the connectors thereof cause the movable swinger pairs such as |11 to be moved to their unrelaXed positions. As a result of such operation the contact swingers |11 will be moved outwardly thereby resulting in the breaking of the circuit which had previously been described from the conductors |19 and |86 through the movable swingers |11 to the conductors IBI and |84, respectively. The dial |18 is thus removed from the circuit.

Upon the movement of the switch or key |16 just described the movable swingers |11 cause conductors |81 and |88 and the right-hand winding of repeater coil |89 to be placed in circuit with the vconductors |84 and |8| leading to the plug |82, jack |83, and outgoing circuit I8. Simultaneously therewith the movable swingers |9| will cause the conductors |92 and |93 and the left-hand winding of the repeater coil |89 to be placed in circuit with a pair of conductors |94 and |90 which connect with the jack |02 and plug |03 associated with the line finder and incoming circuits I3. Thus, a talking circuit will be completed which may be traced from the calling subscribers station l2, through the line iinder district and incoming circuits I3, through the operators cord circuit |18 (particularly the repeater coil |89) and through the outgoing circuits |8 to the called subscriber I9. The telephone conversation may thus progress in the usual manner.

At such time as it is desired to end the call either the called or calling subscriber will replace their receiver upon the hook at their associated station resulting in an immediate breakdown of the interconnecting circuits previously described. One of the rst results of the disestablishment of the telephonie connection will be the de-energization of the relay |04 which will result in the armature |08 no longer being attracted thereto and thus the disestablishment of the circuit which had previously been traced through the armature |06 and over the conductor |14 for the locking current forI the relay I|8. The relay I|8 will immediately de-energ-ize which will result in its armature I|1 being no 'longer attracted and moving to its righthand position, once again completing the circuit between the conductors |I6 and ||9 in readiness for further operation of the line identier II to the operators circuit upon the instigation of another call by a calling subscriber (and energization of the relay |01). Thus, the apparatus is now back to its normal or unoperated position in readiness for another cycle of operation.

While the instant apparatus has been described as utilizing films bearing audible tone frequencies indicative of the exchange and number designa-v tions, it is obvious that other means may be employed, such as magnetic recordings, etc.

Further, while a single calling subscribers station has been described it must be kept in mind that the present invention incorporates line identication for a plurality of calling subscribers stations, as distributors are provided for generating signals for integers in the thousands, hundreds position from 00 to 99 and in the tens, units position similarly. Thus, any combination of a four digit number may be achieved, and various exchange designations may be generated also.

While a specific embodiment of the invention has been illustrated and described it is obvious that the invention'is not limited thereto but that such is merely an embodiment incorporating the spirit of the invention.

What is claimed is:

1. In a line identier, a lm and photocell for generating audible tone signals indicative of an exchange designation of a calling subscriber, a distributor for receiving the signals generated, a plurality of iilms and photocells for generating audible tone signals indicative of the integers 0 and to 9, inclusive, representing the numeral designation of said calling subscriber, a l'lrst group of distributors for receiving signals generated in the thousands, hundreds positions of a number, a second group of distributors for receiving signals generated in the tens, units positions of a number, and means for combining the output of said distributor, one of the distributors in said first group of distributors, and one of the distributors in said second group of distributors, whereby a complete subscriber designation will be achieved.

2. In a telephone system, a calling subscribers station, an operators station, means for interconnecting said stations, a lm and photocell for generating audible tone signals indicative of the exchange designation of said calling subscribers station, a distributor associated with said film and photocell for receiving the signals generated thereby, a plurality of lms and photocells for generating audible tone signals indicative of the numeral designation of said calling subscribers station, a plurality of distributors associated with said plurality of lms and photocells for receiving the signals generated thereby, means for causing the output of said first-mentioned distributor to be impressed directly to said operators station when said stations are interconnected, a cutoff relay, and an additional winding on said cutoi relay cooperating with said plurality of distributors for superimposing the output of said plurality of distributors on said cutoi relay, whereby the signals indicative of the numeral designation of said calling subscribers station are impressed from said cutoff relay to said operators station when said stations are interconnected.

3. In a telephone system, a plurality of calling subscribers stations, each having assigned thereto an exchange designation and a numeral designation, an'operators station,` means for interconne'ctingv each calling subscribers station with said operators station, a lm and a photocell for gen? erating audible tone signals indicative of the exifchange designation of'f'said plurality of calling,

vsubscribers stations, means for receiving the sig.

nais generated thereby, a plurality of :films and photocells for generating audible tone signals inl` dicative of the numeral designations of said plurality of calling subscribers stations, means for selecting and receiving only the signals generated of` said calling subscribers stations is interconnested with said opefators station, a cutoff relay,

3 andan additional winding on said cutoff relay for superimposing the output of said last-mentioned signal receiving means on said cutoff relay, whjerebythe signal indicative of the numeral designation of said calling subscribers station interconnected with said operators station are impressed 2 from said cutoff relay to said operators station when one of said calling subscribers stationsfis interconnected with said operators station.

4. In a line identier for use in telephonev circuits, a plurality of lms and photocells for-Eligi' Y erating audible tone signals indicative of afcalling subscribers station, a distributor for receiving audible tone signals from one of said photocells indicative of the exchange designation, a

plurality of distributors associated with predeter- ,5 mined of said films and photocells for receiving audible tone signals indicative of the subscribers number, means for impressing said audible tone signals indicative of said exchange designation directly to the telephone circuit from said rstmentioned distributor, a cutoi relay, means for impressing said audible tone signals indicative of said subscribers number on said cutoif relay from said plurality of distributors, and means for impressing said audible tone signals indicative of said subscribers number from said cutoff relay to the telephone circuit.

MARTHA W. C. POTTS,

Executri Under the Last Will and Testament 20 of Louis M. Potts, Deceased.

REFERENCES CITED The following references are of record in the le of this patent:

35 UNTTED sTATEs PATENTS 30 2,318,267 Taylor May 4, 1943 

